import { OrbitControls } from '../../node_modules/three/examples/jsm/controls/OrbitControls';//控制器
import { GLTFLoader } from '../../node_modules/three/examples/jsm/loaders/GLTFLoader';//glb模型加载器

import { Mesh, PerspectiveCamera, Scene, WebGLRenderer, PointLight, AmbientLight, AxesHelper,   DoubleSide,  PlaneGeometry, MeshPhongMaterial,  Clock,  AnimationMixer,  GridHelper, Raycaster, Vector2,  Object3D  } from 'three';
export class LightProbeDemo {
    private camera: PerspectiveCamera; 
    private scene: Scene;
    private renderer: WebGLRenderer;
    private gltfLoader:GLTFLoader;
    private animationMixer:AnimationMixer;
    private clock: Clock;
    private action!:AnimationAction;
    constructor() {
        // 创建场景
        this.scene = new Scene();
        this.animationMixer = new AnimationMixer(this.scene); //初始化帧动画混合器
        this.gltfLoader = new GLTFLoader();
        this.clock = new Clock();//初始化时钟对象
        
        // 创建渲染器
        this.renderer = new WebGLRenderer({ antialias: true }); 
        this.renderer.setSize(window.innerWidth, window.innerHeight);
        this.renderer.setPixelRatio(window.devicePixelRatio); //设备像素比 可以清晰物体
        this.renderer.setClearColor(0xb9d3ff, 1); //设置背景颜色
        document.body.appendChild(this.renderer.domElement);

      

        // 创建相机
        this.camera = new PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
        this.camera.position.set(0, 5, 10);
        this.camera.lookAt(this.scene.position);

        // 平面
        const planeGeo = new PlaneGeometry(100, 100);
        const plane = new Mesh(planeGeo, new MeshPhongMaterial({ color:0xffffff, side:DoubleSide }));
        plane.name='plane';
        plane.rotation.x = -Math.PI/2;
        this.scene.add(plane);
        this.scene.add(new GridHelper(100, 100));
        // glb模型加载
        this.gltfLoader.load('../assets/Soldier.glb', gltf=>{
            console.log(gltf);
            gltf.scene.name = 'Soldier'; //标识模型
            this.scene.add(gltf.scene);
            // 获取剪辑clip对象
            const animationClip = gltf.animations.find(animationClip=>animationClip.name==='Walk');
            if(animationClip){
                // 通过混合器的剪辑动作返回一个帧动画的操作对象
                 this.action = this.animationMixer.clipAction(animationClip);
                 this.action.play();//帧动画播放
            }
          
        });

        // 处理点击事件
        this.renderer.domElement.addEventListener('click', e=>{
            // 将鼠标位置归一化为设备坐标。x 和 y 方向的取值范围是 (-1 to +1)
            const x = ( e.clientX / window.innerWidth ) * 2 - 1;
            const y = - ( e.clientY / window.innerHeight ) * 2 + 1;
            const mousePoint = new Vector2(x, y); //拿到鼠标点击的坐标
            
            const raycaster=new Raycaster();
            // 通过摄像机和鼠标位置更新射线
            raycaster.setFromCamera( mousePoint, this.camera );
           const intersects = raycaster.intersectObjects(this.scene.children, true); //第二个参数为true表示递归遍历
            // 判断是否点击在模型上
           const intersect = intersects.filter(intersect=>!(intersect.object instanceof GridHelper) && intersect.object.name!=='plane')[0];
            // 确保只点击在Soldier模型上面
           if(intersect && this.isClickSoldier(intersect.object)){
                this.action.stop();
           }

        });


        // 点光源
        const pointLight = new PointLight(0xffffff, 2);
        pointLight.position.set(100, 200, 100);
        this.scene.add(pointLight);
        // 环境光
        const envlight = new AmbientLight(0xffffff, 2);
        this.scene.add(envlight);
       
        // 辅助坐标系
        var axis = new AxesHelper(250);
        // this.scene.add(axis);
        new OrbitControls(this.camera, this.renderer.domElement);
        window.addEventListener('resize', () => this.onWindowResize());
        this.render();
    }

    private isClickSoldier(object:Object3D) {
        if(object.name=='Soldier'){
            return object;
        }else if(object.parent){
          return this.isClickSoldier(object.parent);
        }else{
            return null;
        }
    }
    private onWindowResize() {
        this.renderer.setSize(window.innerWidth, window.innerHeight);
        this.camera.aspect = window.innerWidth / window.innerHeight;
        this.camera.updateProjectionMatrix(); //相机属性发生变化更新投影矩阵
    }
    private render() {
        this.animationMixer.update(this.clock.getDelta()); //获取两帧之间的时间 然后更新帧动画（这个不写的话不能进行帧动画播放）
        window.requestAnimationFrame(() => this.render());
        this.renderer.render(this.scene, this.camera);
    }

}

three.js中的射线拾取以及坐标转换原理可以参考以下文章：

https://zhuanlan.zhihu.com/p/143642146